Improvement in sewing-machines



G. L. JENKS.

Sewing Machine.

- Patehted Aug. 2, 1859.

horn 5 s ES UNITED STATES PATENT OFFICE.

GEORGE L. J EN GKS, OF PROVIDENCE, RHODE ISLAND, ASSIGNOB 'lO HIMSELF,GEO. KENDALL, AND JOHN KENDRIOK, OF SAME PLACE.

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 24,973, dated August 2,1859.

To all whom it may concern.-

Be it known that I, GEORGE L. Jnnous, of the city of Providence, in thecounty of Provi deuce and State of Rhode Island, have invented a new anduseful Improvement in Sewing-Maehines; and I do hereby declare that thefollowing isa full, clear, and exact description of the same, referencebeing had to the accompanying drawings, making part of thisspecification, in which- Figure 1 represents a front elevation of amachine with myimprovements, but exhibits the table on which the clothis laid in section. Fig. 2 is a vertical section of the same, taken verynear the needle in a plane at right angles to Fig. 1 and transversely tothe movement of the cloth. Fig. 3 represents part of the opposite sideof the machine to that shown in Fig. 2. Fig. 4 represents the cloth,the.

needle, and the thread, and illustrates the stitch-making operation.

Similar letters of reference indicate like parts in the several figures.

This invention relates to those sewing-machines only which employasingle thread and produce therewith a chain-stitch.

The nature of my invention consists, first, in the combination, inasinglethread sewingmachine, ofa perforating barbed needle which isarranged obliquely to the feed movement of the cloth or material beingsewed, with a pair of nippers, or other equivalent device, which will,as the inclined needle is operating to assist in forming the stitch,retain and present the thread to the needle in a manner to allow thenecessary loop to be formed, shortened, and drawn into or tight on thecloth, substantially as set forth in the body of the specification underthe head operation of making the stitch.

It consists, second, in the combination, with a perforating barbedneedle, of the spring uippers, thread-guide, and adjusting nipperclosingbracket, when constructed, arranged, and operating in the mannersubstantially as hereinafter described.

To enable others skilled in the art to make and use my invention, I willproceed to describe its construction and operation.

The machine represented employs a hooked needle.

A is the table, on which the cloth or other material is laid to besewed.

B is a stationary standard, to which is attached a long rigid arm, G,which projects horizontally over the table A, and which has bolted to itor cast with it an inclined frame. H, which contains guides a a for theinclined needle-bar N, and has a foot-piece, I), at the bottom,constituting the pressure-pad, and a spur, c, which serves as aguide tothe feedingdog G.

On the top of the arm 0 are the bearings for the shaft D, which may bedriven by hand or by a band or treadle, and which carries at its frontend a disk, E, on which is an cecentrie wrist-pin, e, which is connectedby the rod F with and drives the needle-bar N. The needle-baroccupiesand moves in a plane perpendicular to the plane of mo tion ofthe cloth and parallel with the direction of said motion, but is obliqueto the latter plane in the former one, the angles formed by it beingabout seventy-five degrees 'and one hundred and five degrees; but suchangle may be varied. The hooked needle n, which has a flexible andelastic barb, works freely through a small hole in the foot-piece I).The feedingdog is forked, and its prongs d d are fitted to slide againstthe horizontal lower surface of the spur c, to which it is confined by aspring, a, fitted to slide on its parallel upper surface. The feedingdoghas a vertical motion to make it bite and disengage itself from thecloth, and a horizontal motion to mov e the cloth, the first beingproduced by a pin,f, attached to the periphery of the disk E, and thesecond by a pin, g, attached to the back of said disk. The pinf actsagainst the side of a lever, I, (see Fig. 3,) which works on a fulcrum,j, secured in the frame H, and whose lower end acts upon a pin, h, whichworks through the spur c,and rests on the upper part of the dog, thesaid pin, as it passes a projection on the lever, causing saidlever toforce down the pin h and force down the dog, and the spring a liftingthe dog again as the pin f works clear of the lever. The pin gacts uponthe forked upper end ofalever, J, which works upon a fulcrum-pin, 70,secured in the frame H, and gives the said lever a vibrating movement,which causesa projection, Z, on its lower extremity to work between theheel of the dog and the point of a screw, on, which is fitted to abracket, m, attached to the said heel, and thus to move the doghorizontally.

The length of the horizontal movement of the dog is varied by adjustingthe screw m so as to give the lever more or less play between it and theheel of the dog. The feed is in the direction of the arrow shown in Fig.1-viz., toward that side of the needle which forms the greatest angleabove the table A or plane of motion of the cloth, and the barb of theneedle is on that side. The pressure-pad b is unyielding, but an elasticpressure is obtained by making an opening in the table A below thesaidpad and thedog, and fitting the said opening with a plate, A, which hasa strong spring applied to hold it up, the upper surface of the saidplate projecting slightly above the surface of the table A.

K is a box placed below the table A to contain a ball or loose spool ofthread. The thread passes from the said box through a frictionclamp, L,which is arranged nearly in the vertical plane of the feed on that sideof the needle toward which the cloth moves. M M are thenippers,arr'anged below the said table,between the said clamp and theline of motion of the needle. The lower jaw of said nippers is formed ona sliding bar, M, which is fitted to work transversely to the directionof the feed motion in guides N N, the latter of which is fitted with asetscrew, P, to permit the adjustment of that end of the said bar whichconstitutes the jaw higher or lower.-

The upper jaw is made of spring-steel and secured to the bar M, and itselasticity is such that it will open when permitted to do so. It iscurved in such a way that it will be closed by coming in contact withthe upper part of the guide N as it is carried by the bar N through thesaid guide in the direction of the arrow shown on said bar in Fig. 2. ais the thread-guide for laying the thread across the needle, that it maybe caught by the bail) thereof, said guide being attached to the bar M.The bar M derives its longitudinal motion to operate the nippers and thethreadguide from a lever, Q, working on a fulcrum, attached to one sideof the standard B, said lever being actuated partly by a cam, R, on theshaft D, and said lever being kept in contact with the cam by a spring,S, applied to the bar M.

The operation of making the stitch is as follows: The greater portionof-the descending movement of the needle is made while the nippers M Mand threadguide n are stationary in the position and condition shown inFig. 2that is to say, at the end of their advancing movement, and thenippers being open. As the needle completes its descent the nippers andthread-guide retreat in the direction of the arrow shown on the bar M,and while the nippers close upon the thread the guide 12 leads it acrossthe path of the needle, so

that as the latter ascendsit catches the thread and draws it'through thecloth in the form of a loop, the barb of the needle being closed as itrises by passing through the small conical opening r (see Fig. 1) in theplate A. p

The nippers and thread-guide remain stationary during the greater partof the ascent of the needlethat is to say, till the point of thebarb haspassed through the clothbut they advance again and openduring thecompletion of the said ascent, then again remain station ary, as atfirst described,till the needle is completing its descent, when theyretreat again and the nippers close to carry the thread across the pathof the needle, that it may be drawn up again through the cloth in theform of a loop, which is also drawn through the first loop, the nippersin this latter movement gripping the thread and drawing back through thecloth nearly all the slack of the first loop, the tightening of which iscompleted by the needle in drawing up the second one,while the nippers,still advancing, continue to grip the thread; but before the ascent ofthe needle has been completed the nippers are permitted to open, so thatthe needle in completing its ascent will draw through the friction-clampL the quantity of thread necessary to make astitch. The production of aseam is but the repetition of this operation.

The effect of the oblique arrangement of the needle, hereinbeforedescribed, is illustrated in Fig. 4, which represents in one view, on alarger scale than the other figures, the cloth, the needle, and twostitches in course of formation, both by the perpendicular and obliquearrangements of the needle, the operation of the loops under theperpendicular arrangement being represented in dotted and that under theoblique arrangement in bold outline, the thread being in both casesshown in red color, and the needle in both cases being supposed to havepassed through the center of the thickness of the cloth at the samepoint. By a comparison of the positions of the loops u it (representedon the two needles) and the loops 1) 2;, through which the first-namedloops have passed, it will be seen that the loop a on theobliquelyarranged needle allows the loop '12 through which it passes tobe drawn up much shorter in the act of drawing the new loop through thecloth than is permitted to theloop vthrough which theperpendicularly-arranged needle has drawn its loop, and itis this thatpermits the stitch to be drawn tighter, for after the loop has beenshortened in this way it is easily drawn down into the cloth as the nextsucceeding loop is being drawn tight by its successor.

The advantage of this improvement has been demonstrated by theproduction of a tight seam with thread of such a poor quality as wouldnot permit its use in any other machine.

I do not claim, generally, the arrangement of needles obliquely to theplane of the feeding movement of the cloth, as I am aware that such anarrangement of two needles has been employed in Averys and othersewing-machines, and that one of two needles'has been so arranged in themachine of T. J. W. Robertson, Patent No. 18,740; but in no case doesthe so-arranged needle produce such an action upon or in relation withitsown thread as that produced by my arrangement of the needle in asingle-thread chainstitch machine.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. The combination, in a singlethread sewing-machine, of a perforatingbarbed needle which is arranged obliquely to the feed movement of thecloth or material being sewed,with a pair of nippers or other equivalentdevice,

'nstin ni er-closin bracket when cona pp 0 structed, arranged, andoperating substantially as and for the purposes set forth.

GEORGE L. JENGKS.

\Vitnesses:

WM. Tuscan, W. IIAUFF.

